From c5cc43d3eb476ba7d05141507615e79b0741a728 Mon Sep 17 00:00:00 2001
From: antoinegaston <antoine@epigenelabs.com>
Date: Fri, 16 Jan 2026 09:41:37 +0100
Subject: [PATCH 1/2] =?UTF-8?q?=F0=9F=90=9B=20Fix=20obstore=20listdir=20me?=
 =?UTF-8?q?thod=20using=20=5Frelativize=5Fpath?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 src/zarr/storage/_obstore.py | 12 ++++++++----
 src/zarr/testing/store.py    | 36 ++++++++++++++++++++++++------------
 2 files changed, 32 insertions(+), 16 deletions(-)

diff --git a/src/zarr/storage/_obstore.py b/src/zarr/storage/_obstore.py
index 5c2197ecf6..6e4011da59 100644
--- a/src/zarr/storage/_obstore.py
+++ b/src/zarr/storage/_obstore.py
@@ -4,6 +4,8 @@
 import contextlib
 import pickle
 from collections import defaultdict
+from itertools import chain
+from operator import itemgetter
 from typing import TYPE_CHECKING, Generic, Self, TypedDict, TypeVar
 
 from zarr.abc.store import (
@@ -15,6 +17,7 @@
 )
 from zarr.core.common import concurrent_map
 from zarr.core.config import config
+from zarr.storage._utils import _relativize_path
 
 if TYPE_CHECKING:
     from collections.abc import AsyncGenerator, Coroutine, Iterable, Sequence
@@ -263,10 +266,11 @@ async def _transform_list_dir(
     # We assume that the underlying object-store implementation correctly handles the
     # prefix, so we don't double-check that the returned results actually start with the
     # given prefix.
-    prefixes = [obj.lstrip(prefix).lstrip("/") for obj in list_result["common_prefixes"]]
-    objects = [obj["path"].removeprefix(prefix).lstrip("/") for obj in list_result["objects"]]
-    for item in prefixes + objects:
-        yield item
+    prefix = prefix.rstrip("/")
+    for path in chain(
+        list_result["common_prefixes"], map(itemgetter("path"), list_result["objects"])
+    ):
+        yield _relativize_path(path=path, prefix=prefix)
 
 
 class _BoundedRequest(TypedDict):
diff --git a/src/zarr/testing/store.py b/src/zarr/testing/store.py
index ad3b80da41..454a58af9e 100644
--- a/src/zarr/testing/store.py
+++ b/src/zarr/testing/store.py
@@ -491,24 +491,36 @@ async def test_list_empty_path(self, store: S) -> None:
         assert observed_prefix_sorted == expected_prefix_sorted
 
     async def test_list_dir(self, store: S) -> None:
-        root = "foo"
-        store_dict = {
-            root + "/zarr.json": self.buffer_cls.from_bytes(b"bar"),
-            root + "/c/1": self.buffer_cls.from_bytes(b"\x01"),
-        }
+        roots_and_keys: list[tuple[str, dict[str, Buffer]]] = [
+            (
+                "foo",
+                {
+                    "foo/zarr.json": self.buffer_cls.from_bytes(b"bar"),
+                    "foo/c/1": self.buffer_cls.from_bytes(b"\x01"),
+                },
+            ),
+            (
+                "foo/bar",
+                {
+                    "foo/bar/foobar_first_child": self.buffer_cls.from_bytes(b"1"),
+                    "foo/bar/foobar_second_child/zarr.json": self.buffer_cls.from_bytes(b"2"),
+                },
+            ),
+        ]
 
         assert await _collect_aiterator(store.list_dir("")) == ()
-        assert await _collect_aiterator(store.list_dir(root)) == ()
 
-        await store._set_many(store_dict.items())
+        for root, store_dict in roots_and_keys:
+            assert await _collect_aiterator(store.list_dir(root)) == ()
 
-        keys_observed = await _collect_aiterator(store.list_dir(root))
-        keys_expected = {k.removeprefix(root + "/").split("/")[0] for k in store_dict}
+            await store._set_many(store_dict.items())
 
-        assert sorted(keys_observed) == sorted(keys_expected)
+            keys_observed = await _collect_aiterator(store.list_dir(root))
+            keys_expected = {k.removeprefix(root + "/").split("/")[0] for k in store_dict}
+            assert sorted(keys_observed) == sorted(keys_expected)
 
-        keys_observed = await _collect_aiterator(store.list_dir(root + "/"))
-        assert sorted(keys_expected) == sorted(keys_observed)
+            keys_observed = await _collect_aiterator(store.list_dir(root + "/"))
+            assert sorted(keys_expected) == sorted(keys_observed)
 
     async def test_set_if_not_exists(self, store: S) -> None:
         key = "k"

From 99990a80efbe1dd3ecc14e674c8442de76f8628e Mon Sep 17 00:00:00 2001
From: antoinegaston <antoine@epigenelabs.com>
Date: Fri, 16 Jan 2026 11:03:30 +0100
Subject: [PATCH 2/2] =?UTF-8?q?=F0=9F=93=9D=20Add=20changelog=20entry?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 changes/3657.misc.md | 1 +
 1 file changed, 1 insertion(+)
 create mode 100644 changes/3657.misc.md

diff --git a/changes/3657.misc.md b/changes/3657.misc.md
new file mode 100644
index 0000000000..1411704674
--- /dev/null
+++ b/changes/3657.misc.md
@@ -0,0 +1 @@
+Fix obstore _transform_list_dir implementation to correctly relativize paths (removing lstrip usage).
\ No newline at end of file